Date of Award

January 2013

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Biology

First Advisor

Jefferson Vaughan

Abstract

In 2010 a statewide survey of ticks and tick-borne pathogens was conducted in North Dakota. Ticks were collected from the four eco-regions in the state by flagging for questing adults and by collecting feeding immature ticks from trapped small mammals. I collected 1762 individual ticks representing five species: Dermacentor variabilis (1449), Ixodes scapularis (307), Ixodes woodi (3), Ixodes angustus (2), and Amblyomma americanum (1). Dermacentor variabilis were collected in all areas of the state while I. scapularis were restricted to the northeast portion of the state. This provided sufficient evidence that I. scapularis have established populations within the state. Ixodes scapularis were tested for Borrelia burgdorferi (the agent of Lyme disease), Anaplasma phagocytophilum (agent of human granulocytic anaplasmosis), and Babesia microti (agent of human babesiosis). Of those tested, A. phagocytophilum was detected in 8.5%, B. burgdorferi was detected in 3.3%, and B. microti was not detected. These are the first reports of A. phagocytophilum and B. burgdorferi detected in the wild in North Dakota and provide evidence of westward range expansion of these organisms.

To determine the areas that the ticks were moving into, a study was conducted in Grand Forks County, ND in 2012 to determine the effects of forest patch size on the abundance of adult questing and immature host-feeding I. scapularis and the prevalence of A. phagocytophilum, B. burgdorferi, and B. microti in those ticks. Increased forest patch size was significantly correlated with increased abundance of adult questing ticks and larval ticks collected from small mammals. Few I. scapularis were collected from the four smallest sites limiting the ability of pathogens to become established. Among the two largest sites there was not a significant difference in the prevalence of B. burgdorferi or A. phagocytophilum detected in questing adults or xeno-positive small mammals.

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